Tube scraper



H. J. SIEVERS 2,395,019

TUBE S CRAPER Filed April 10, 1942 IN V EN TOR.

Patented Feb.19 1946 v UNITED STATES PATENT OFFICE TUBE SCRAPER Henry J.Sievers, Evanston, Ill.

Application April 10, 1942, Serial No. 438,391

3 Claims.

This invention relates to cleanin or scraping devices for tubes such asfiues, boiler tubes. and the like.

It is an object of the invention to provide a tube scraper of the typedefined, of simplified construction, which may be readily andeconomically fabricated. and which will be efficient in operation.

More specifically, it is an object of the invention to provide in a tubescraper of the type defined, improved and simplified means for adlustingthe scraper blades to compensate for wear and to apply a' predeterminedscraping engagement against the tube surface, while permitting automaticresilient contraction of the scraper blades as may be necessary to clearobstructions or the like within the tube.

A further object of the invention is to provide a tube scraper ofsimplified structure wherein the scraper blades form substantiallycontinuous circumferential contact with the tube wall, while at the sametime being readily adjustable in a radial direction to accommodate thetube size and. to provide increased or decreased pressure contactingengagement against the tube wall.

A still further object of the invention is to" provide scraper bladeswhich are self-sharpening.

Various other objects, advantages and features of the invention will beapparent from the following specification when taken in connection withthe accompanying drawing wherein a preferred embodiment of the inventioni set forth for purposes of illustration.

In accordance with the invention, the scraping unit of the structurecomprises in effect a substantially one-piece element providingcircumferentially continuous contactin engagement against the tubesurface, the scraper blades being readily adjustable and resilientlymounted to provide the necessary movements for the blades in a radialdirection.

In the drawing, wherein like reference numerals refer to like partsthroughout:

Fig. 1 is a general assembly view of a scraper structure constructed inaccordance with the scraper on the line 3-3 of Fig. 2 and Fig. 4 is aperspective view of the scraping unit or element 01' the structure.

Referring more specifically to the drawing, the

scraper, shown in association with a tube It to be scraped. comprises anoperating rod II, a support shaft or mandrel l2 mounted on the end ofthe operating rod, and a scraping unit, generally indicated by thenumeral I3, supported by the shaft l2. The operating rod I i may be ofany desiredlength, to extend beyond the end of the tube In, and form themeans by which the scraper structure may be propelled longitudinally ofthe tube to effect its cleaning or scraping functions.

More specifically, the support shaft i2 is carried on the end of the rodH by means of a coupling member it provided with threaded sockets oneither end-thereof,-into which the rod ii and shaft I? are threadedlysecured. A pin it, pressfitted into position, serves to preventinadvertent unthreading of the shaft H from the coupling member, afterassembly of the parts. Suitable means, such as a lock nut l6, may beprovided for maintaining the coupling member in locked position upon theend of the operating rod. The pin l5 also acts as a securing means for asheet metal guiding cone if, the apex end of which is formed with acylindrical skirt I 8 arranged in embracing relation upon the end of thecoupling member. A washer l9 loosely mounted on the shaft I2, ismaintained in engagement with the end of the coupling member by theresilient engagement of the scraping unit, this washer bein soproportioned that it acts as a position maintaining means for theguiding cone. The guiding cone facilitates the entrance of the scraperstructure into the end of the tube, remote from the operating rod H, theright end of the tube as seen in Figs. 1 and 2. The enlarged end l'la ofthe cone is somewhat smaller than the diameter of the tube, so as not tointerfere with the ready introduction of the scraper into the oppositetube end, or to the left as seen in Figs. 1 and 2.

The scraping unit, which is perhaps best illustrated in Fig. 4,comprises a series of scraper blades 25, and a cooperating series ofblades 26, the juxtaposed ends of which are secured together by suitablemeans, such as welding or riveting, rivets 2'! being the securing meansillustrated in the particular embodiment shown. Also in the particularillustrated embodiment there are four blades 25, and four blades 28,which The ends of the blades 25, extending ,away from the blades 28. aresecured to a support bracket to adapted to be loosely mounted on theshaft ii, The projecting ends of the blades 26 are similarly secured toa support bracket II, also adapted to be loosely mounted on shaft l 2.More specifically, bracket 30 is provided with a series of flanges orwings 30a, to the undersides of which the blades 25 are respectivelysecured, bracket 3| being similarly provided with flanges or wings 3 lafor supporting the ends of the blades 28. Any suitable means may beemployed for securing the blades to the support brackets, rivets 32being illustrated as the securing means in the particular embodimentshown.

As best shown in Fig. 2, the outer end of the support shaft I2 isthreaded as indicated at I211, this threaded shaft section being adaptedto support a wing nut or the like 33 and a washer member 34. Byadjustment of the wing nut 33, washer 34 is thrust into engagement withthe support bracket 30, which in turn urges the support bracket 3| intoabutting engagement with the washer l9. By means of the wing nut thesupport bracket 30 may be adjusted longitudinally on the shaft l2whereby, due to the shaping of the scraper blades, the scraping edges25a and 26a thereof are adjusted in a radial direction for predeterminedscraping contact against the tube wall. If desired, a lock nut or thelike 35 may be provided for holding the wing nut 33 in adjustedposition.

Particular attention is directed to the shaping and disposition of thescraper blades. It will be noted that the blades are of generally curvedshape whereby, due to their spring tempered character they may beresiliently urged radially into engagement with the tube wall byadjustment of the wing nut 33, Also due to the resilient thrustingengagement thus provided, the blades may be automatically slightlycontracted radially upon engagement with unusual or obstinateobstructions in the tube to effect a clearance thereof as may benecessary, notwithstanding the, fact that the adjustment of the nut 33may be such as to urge the blades firmly into engagement with the tubewall. Further, compensations for wear may be readily effected byadjustment of the wing nut 33, and adjustments may also be made, withinlimits, to adapt the scraper to different sized tubing. It willaccordingly be seen that while the scraper unit is in effect ofsimplified one-piece construction, it is possessed of efficient andadvantageous operating characteristics desirable in a device of the typedescribed. The scraper unit may be readily and economically fabricatedas an essentially one-piece unit.

It will further be noted, particularly by preference to Fig. 4, that theblades 25 overlap the junctures or spaces between the blades 28, andthat the blades 28 similarly overlap the junctures or spaces between theblades 25, so that the scraping edges 25a and 28a of the two sets ofblades provide a circumferentially continuous scraper structureengageable with the tube wall. This circumferentially continuousstructure, while in effect of one-piece construction, is at the sametime radially adjustable as heretofore pointed out. The spring steelblades, which are relatively thin, provide effective scraping edges 25aand 26a, without the necessity for special sharpening or edge producingdevices, and the edges will automatically remain sharp regardless ofwear as the structure continues in use.

As is believed to be clear, after proper adjustment of the wing nut 33,the scraper structure is operated by the operating rod II, to effect itslongitudinal propulsion through the tube, thereby effecting its scrapingand cleaning functions by reason of the engagement of the scraper bladesagainst the tube wall surface. The guiding cone l1 facilitatesintroduction of the scraper into the tube end remote from the operatingrod II, as may be necessary.

It is obvious that various changes may be made in the specificembodiment illustrated without departing from the spirit of theinvention. Accordingly, the invention is not to be limited to thespecific embodiment shown and described but only as indicated in thefollowing claims,

The invention is hereby claimed as follows:

1. A tube scraper including in combination an elongated support, aplurality of sets of scraper blades supported thereb adjacent respectiveends of the scraper blades, the other ends of said blades being formedwith outwardly directed flange portions wider than the supported ends,said flange portions of opposite blades having parts in juxtaposition,and means for rigidly uniting the flange portions of opposite blades ina set.

2. A tube scraper including in combination an elongated support, aplurality of sets of scraper blades supported thereby adjacentrespective ends of the scraper blades, the other ends of said bladesbeing formed with outwardl directed flange portions wider than thesupported ends, said flange portions of opposite blades having parts injuxtaposition, means for rigidly uniting the flange portions of oppositeblades in a set, and means adjustable on said support member forimparting longitudinal thrust to said sets of blades to move saidflanges outwardly.

3. A tube scraper including in combination an elongated support, aplurality of sets of scraper blades supported thereby adjacentrespective ends of the scraper blades, the other ends of said bladesbeing formed with outwardly directed flange portions wider than thesupported ends, said flange portions of opposite blades having parts injuxtaposition, and means for rigidly uniting the flange portions ofopposite blades in a set, flange portions of adjacent sets having partsof the flange portions overlapping whereb to provide a circumferentiallycontinuous scraper surface.

HENRY J. SEVERE.

